1. Field of the Invention
The invention relates to the field of LED lighting, and more particularly to a liquid-cooled LED illuminating lamp.
2. Description of the Related Art
LED, called the fourth-generation lighting source or green lighting source, with characteristics of energy saving, environmental protection, long life, and small size, is widely applied in various fields such as indicating, display, decorating, backlight source, general lighting and urban night-landscaping and etc.
LED light-emitting chips emit light by electronic recombination. In the case of small current, it produces little heat, but in a high-power LED illuminating lamp, especially in the field of lighting applications, great current is required, thus a lot of heat is generated and the operating temperatures are high. The main factor affecting the LED light-emitting chip is the temperature (the operating temperature of PN node), and the operating temperature of PN node is generally no higher than 120 degrees, preferably at about 100 degrees. When the temperature of PN node rises by every 10 degrees, the luminous flux decreases by 1%, the main light-emitting wavelength drifts by 1 nm, and the life is shortened accordingly. Therefore, heat dissipation of the LED is a problem that must be considered.
In addition, the volume of LED light-emitting chips is very small, and it is the point light-emitting, with high directivity (the light of LED light-emitting chip emitted is linear, the divergence is not good), which generally leads to a relatively small irradiation angle. To solve the problems of the relatively small irradiation angle, the lamp tube-type LED lighting is used, which has dense lamp array, high design costs, and poor cooling and energy-saving effect.